Exploring high-throughput synchrotron X-Ray powder diffraction for the structural analysis of pharmaceuticals.

Synchrotron radiation offers a host of advanced properties, surpassing conventional laboratory sources with its high brightness, tunable phonon energy, photon beam coherence for advanced X-ray imaging, and a structured time profile, ideal for capturing dynamic atomic and molecular processes. However, these benefits come at the cost of operational complexity and expenses. Three decades ago, synchrotron radiation facilities, while technically open to all scientists, primarily served a limited community. Despite substantial accessibility improvements over the past two decades, synchrotron measurements still do not qualify as routine analyses. The intrinsic complexity of synchrotron science means experiments are pursued only when no alternatives suffice. In recent years, strides have been made in technology transfer offices, intermediate synchrotron-based analytical service companies, and the development of high-throughput synchrotron systems at various facilities, reshaping the perception of synchrotron science. This article investigates the practical application of synchrotron X-Ray Powder Diffraction (s-XRPD) techniques in pharmaceutical analysis. By utilizing concrete examples, we demonstrate how high-throughput systems have the potential to revolutionize s-XRPD applications in the pharmaceutical industry, rapidly generating XRPD patterns of comparable or superior quality to those obtained in state-of-the-art laboratory XRPD, all in less than 5 s. Additional cases featuring well-established pharmaceutical active ingredients (API) and excipients substantiate the concept of high throughput in pharmaceuticals, affirming data quality through structural refinements aligned with literature-derived unit cell parameters. Synchrotron data need not always be state-of-the-art to compete with lab-XRPD data. The key lies in ensuring user-friendliness, reproducibility, accessibility, cost-effectiveness, and the streamlined efforts associated with synchrotron instrumentation to remain highly competitive with their laboratory counterparts.

Evolution of Magnetic Order from the Localized to the Itinerant Limit.

Quantum materials that feature magnetic long-range order often reveal complex phase diagrams when localized electrons become mobile. In many materials magnetism is rapidly suppressed as electronic charges dissolve into the conduction band. In materials where magnetism persists, it is unclear how the magnetic properties are affected. Here we study the evolution of the magnetic structure in Nd_{1-x}Ce_{x}CoIn_{5} from the localized to the highly itinerant limit. We observe two magnetic ground states inside a heavy-fermion phase that are detached from unconventional superconductivity. The presence of two different magnetic phases provides evidence that increasing charge delocalization affects the magnetic interactions via anisotropic band hybridization.

Giant Pressure Dependence and Dimensionality Switching in a Metal-Organic Quantum Antiferromagnet.

We report an extraordinary pressure dependence of the magnetic interactions in the metal-organic system [CuF_{2}(H_{2}O)_{2}]_{2}pyrazine. At zero pressure, this material realizes a quasi-two-dimensional spin-1/2 square-lattice Heisenberg antiferromagnet. By high-pressure, high-field susceptibility measurements we show that the dominant exchange parameter is reduced continuously by a factor of 2 on compression. Above 18 kbar, a phase transition occurs, inducing an orbital re-ordering that switches the dimensionality, transforming the quasi-two-dimensional lattice into weakly coupled chains. We explain the microscopic mechanisms for both phenomena by combining detailed x-ray and neutron diffraction studies with quantitative modeling using spin-polarized density functional theory.

Reversible pressure pre-amorphization of a piezochromic metal-organic framework.

The piezochromic metal-organic framework Co2(Bdc)2Dabco·4DMF·H2O (Bdc denotes 1,4-benzenedicarboxylate, Dabco - 1,4-diazabicyclo[2.2.2]octane, and DMF - dimethylformamide) under ambient conditions is tetragonal (phase α) and at about 1.9 GPa undergoes a strong pressure-induced shortening of translational correlations in the sample. A broad gradual pre-amorphization process starting at about 0.7 GPa reduces the tetragonal symmetry and is described as phase ß. The pre-amorphization mechanism involves several competing distortions of the Bdc linkers and Co(ii)-coordination schemes. These in turn, affect the crystal field around the cations and their optical absorption. The compression strongly affects the VIS absorption of this piezochromic compound visibly changing its colour from blue to red.

Classical Spin Nematic Transition in LiGa_{0.95}In_{0.05}Cr_{4}O_{8}.

We present the results of a combined ^{7}Li-NMR and diffraction study on LiGa_{0.95}In_{0.05}Cr_{4}O_{8}, a member of the LiGa_{1-x}In_{x}Cr_{4}O_{8} "breathing" pyrochlore family. Via specific heat and NMR measurements, we find that the complex sequence of first-order transitions observed for LiGaCr_{4}O_{8} is replaced by a single second-order transition at T_{f}=11 K. Neutron and x-ray diffraction rule out both structural symmetry lowering and magnetic long-range order as the origin of this transition. Instead, reverse Monte Carlo fitting of the magnetic diffuse scattering indicates that the low-temperature phase may be described as a collinear spin nematic state, characterized by a quadrupolar order parameter. This state also shows signs of short-range order between collinear spin arrangements on tetrahedra, revealed by mapping the reverse Monte Carlo spin configurations onto a three-state color model.

New magnetic frameworks of [(CuF2(H2O)2)(x)(pyz)].

Pressure-driven orbital reordering in the quantum magnet [CuF2(H2O)2(pyz)], (pyz = pyrazine), dramatically affects its magnetic exchange interactions. The crystal chemistry of this system is enriched with a new phase above 3 GPa, surprisingly concomitant with other polymorphs. Moreover, we discovered an unprecedented compound with a different stoichiometry, [(CuF2(H2O)2)2(pyz)], featuring magnetic bi-layers.

The Materials Science beamline upgrade at the Swiss Light Source.

The Materials Science beamline at the Swiss Light Source has been operational since 2001. In late 2010, the original wiggler source was replaced with a novel insertion device, which allows unprecedented access to high photon energies from an undulator installed in a medium-energy storage ring. In order to best exploit the increased brilliance of this new source, the entire front-end and optics had to be redesigned. In this work, the upgrade of the beamline is described in detail. The tone is didactic, from which it is hoped the reader can adapt the concepts and ideas to his or her needs.